• The Korea Journal of Herbology
• /
• v.29 no.6
• /
• pp.1-6
• /
• 2014

Objectives : This study was aimed to compare Gyejibokryeong-hwan (GBH) decoctions produced using different pressure levels for various extraction times to find the optimal extraction conditions through extraction yield, total soluble solids content (TSSC), hydrogen ion concentration (pH), and the contents of chemical compounds. Methods : Decoctions of GBH were prepared under the pressure levels of 0 or $1kgf/cm^2$ for 30-180 min using water as extraction solvent. The extraction yield, TSSC, and pH were measured, and the amounts of the chemical compounds were determined using high performance liquid chromatography-photodiode array detector. Results : The higher pressure and longer extraction time increased the values of TSSC and extraction yield, while decreased the pH value. The decoctions produced in 180 min by pressurized method and produced in 150 min by non-pressurized method showed maximum values of extraction yield and TSSC with minimum value of pH. The amounts of chemical compounds showed variations in pressurized and non-pressurized decoction during overall extraction times. The influences of pressure and extraction time on extraction yield, TSSC, pH, and the contents of chemical compounds were confirmed by regression analysis, which showed that all extraction values were significantly affected by at least one of two extraction factors, pressure and extraction time. Conclusions : This study suggests that the pressure and extraction time can significantly affect the extraction efficiency of components from GBH decoctions. However, optimal extraction conditions could not be chosen due to the variation of the amounts of chemical compounds.

• Journal of Ginseng Research
• /
• v.40 no.3
• /
• pp.229-236
• /
• 2016

Background: Extraction conditions greatly affect composition, as well as biological activity. Therefore, optimization is essential for maximum efficacy. Methods: Korean Red Ginseng (KRG) was extracted under different conditions and antioxidant activity, extraction yield, and ginsenoside Rg1 and phenolic content evaluated. Optimized extraction conditions were suggested using response surface methodology for maximum antioxidant activity and extraction yield. Results: Analysis of KRG extraction conditions using response surface methodology showed a good fit of experimental data as demonstrated by regression analysis. Among extraction factors, such as extraction solvent and extraction time and temperature, ethanol concentration greatly affected antioxidant activity, extraction yield, and ginsenoside Rg1 and phenolic content. The optimal conditions for maximum antioxidant activity and extraction yield were an ethanol concentration of 48.8%, an extraction time 73.3 min, and an extraction temperature of $90^{\circ}C$. The antioxidant activity and extraction yield under optimal conditions were 43.7% and 23.2% of dried KRG, respectively. Conclusion: Ethanol concentration is an important extraction factor for KRG antioxidant activity and extraction yield. Optimized extraction conditions provide useful economic advantages in KRG development for functional products.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.1
• /
• pp.23-28
• /
• 1985

The extraction rate of lipids from the chopped whole fish was studied with various solvents. Factors which can influence on the extraction rate such as temperature, moisture content, agitation speed and solvent were also examined. In the early stage of extraction, it is considered that the rapid extraction was attributed to cell destruction which occurs in chopping the whole fish and in the later stage, the extraction rate was increased linearly with extraction time. The effect of agitation on the extraction rate had a great influence on the early stage of extraction. In agitation speed of 100, 200, 300 and 500 r.p.m. the slopes of extraction curve were -0.075, -0.075, -0.069 and -0.064, respectively. Extractability between hydrophilic and hydrophobic solvent showed a great difference. It is suggested that extractability difference between acetone and isopropyl alcohol is due to acetone property which can not extract phospholipids in polar lipids. Extractability of lipids was increased with increasing temperature and decreased with increasing moisture content.

• Journal of Applied Biological Chemistry
• /
• v.55 no.3
• /
• pp.149-156
• /
• 2012

The effects of solvent type and concentration, solid/liquid ratio, extraction time and repeated extraction on recovery of keratinase from solid-state fermentation (SSF) of chicken feather by a local Streptomyces sp. NRC 13S were investigated in order to establish the experimental conditions for keratinase yield. Among solvents tested, 0.5% (v/v) glycerol was the best. Box-Behnken design was used to investigate the effect of relevant variables on keratinase recovery. The factors investigated were solid/liquid ratio (1:1.66-1:6.66 g/mL), glycerol concentration (0.5-5% v/v) and repeated extraction (1-5 cycle). The results showed that the maximum recovery of keratinase (6933.3 U/gfs) was obtained using 0.5 (v/v) glycerol as extracting solvent, in a solid/liquid ratio of 1:5 and three extraction cycles.

• Journal of the Korea Convergence Society
• /
• v.10 no.12
• /
• pp.429-436
• /
• 2019

This study used raw data from the 2013-2015 National Health and Nutrition Survey, and conducted a multivariate logistic regression analysis to identify factors related to teeth extraction from Korean elderly aged 65 and older (4.037). As a result, the risk of tooth extraction was 1.84 times higher in males, 1.52 times in age 75 or older, 2.36 times higher in income, 2.04 times higher in income, and 1.44 times higher in smokers. The results were statistically significant as 1.49 times without oral examination and 2.30 times without dental treatment for 1 year. Through this, the current health behavior and oral health behavior can reinforce the basis of risk factors related to the need for tooth extraction. At the national level, we need to look for diversification.

• Korean journal of food and cookery science
• /
• v.23 no.6
• /
• pp.954-960
• /
• 2007

The study was designed to determine optimum extraction conditions, by the factorial design of 3 variables and 3 levels using an a RSM program. To determine the optimal conditions for the extraction of black tea with chamomile, the experimental design was applied. The independent factors were the extraction temperature ($60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$), extraction time (2 min, 4 min, 6 min), and chamomile addition (0.3%, 1.0%, 1.7%). By the RSM (response surface methodology) analysis of the black tea with chamomile extraction, we found that the extraction temperature greatly affected the extraction yield, brix, pH, and reducing sugar, caffeine, theobromine and theophillin contents. The optimum extraction time, temperature, and chamomile content were 4 min, $90^{\circ}C$, and $1.6{\sim}1.7%$, respectively.

• Resources Recycling
• /
• v.7 no.5
• /
• pp.3-12
• /
• 1998

The most recent research in precious metal processing is found in the increasing use of heap leaching for the extraction of gold from low grade ores and tailing dumps because heap leaching has several advantages compared to traditional milling. They include simplicity, lower capital and operating costs, faster starter-up time and environmental safety. In this paper, an attempt has been made to provide an overview of important factors involved in the implementation of heap leaching technology as a vehicle for gold extraction from its low grade ores. Brief discussions of the various important elements to this process has been made to ascertain the heap leaching characteristics, such as heap leaching chemistry, natural factors, ore preparation, heap and pad construction, solution collection system, pond system, metal extraction, and economical consideration.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2023.04a
• /
• pp.42-42
• /
• 2023

Paeonia lactiflora roots (PLR) are a traditional medicinal plant used to treat inflammatory diseases. Recently, PLR has been reported to increase the secretion of immune regulatory factors and enhance phagocytic activity in macrophages. Therefore, in this study, we compared the macrophage activation induced by PLR under different extraction conditions. PLR extracts at temperatures ranging from 4℃ to 60℃ increased the secretion of immune regulatory factors, but the secretion slightly decreased at 80℃. Under time-based extraction conditions at 60℃, immune regulatory factor secretion by PLR extracts was similar from 1 to 24 hours. Therefore, considering the overall results of this study, extracting PLR at 60℃ for 1 hour is considered the optimal condition for macrophage activation.

• Journal of Life Science
• /
• v.10 no.2
• /
• pp.202-209
• /
• 2000

The factors affecting chemical composition of green tea (Camellia sinensis L.) during extraction process were temperatures and times. The optimum extraction conditions were measured in relation to the changes of chemical compositions from water extracts of green tea (Camellia sinensis L.) under different extraction temperatures (50, 70, 9$0^{\circ}C$) and extraction times (1, 3, 5 minute). The change of color intensity during browning reaction, flavonoid components, contents of total phenols and hydrogen donating activity (reducing activity for $\alpha$, $\alpha$'-diphenyl-$\beta$ -picryhydrazyl) of water extracts form green tea increased as extraction temperatures increased from 50 to 9$0^{\circ}C$ and extraction times prolonged from 1 to 5 min. The contents of important free sugars such as sucrose and glucose slightly increased as the extraction time was prolonged, while little difference in the content of fructose with the prolonged extraction time. Catechins contents extracted from the commercial steamed green tea were increased at higher temperature and longer extraction time. Epigallocatechin (EGC) extracted from 9$0^{\circ}C$ (extraction time 5 min). presented 99.9 mg/g in highest composition of catechin followed by epigallocatechin gallate (EGCg), epicatechin (EC), epicatechin gallate (ECg). The content of vitamin C extracted from green tea was increased about 2 times as the extraction temperature increased from 50 to 9$0^{\circ}C$ and as the extraction time increased from 1 to 5 min. with exception at 9$0^{\circ}C$(extraction time:5 min) which showed less vitamin C content than 7$0^{\circ}C$(extraction time : 3 min) probably due to possible destruction of vitamin C by high temperature.

• Proceedings of the Optical Society of Korea Conference
• /
• 2008.02a
• /
• pp.355-356
• /
• 2008

The light extraction efficiencies of GaN-based light-emitting diodes (LEDs) grown on differently patterned sapphire substrates were investigated by using the ray tracing method. It was found that angle of the pattern surface against the sapphire surface, the number of pattern per unit area were important structural factors for high extraction efficiency.